A multigigahertz probe is used as a wafer probe for microwave frequencies for performing on wafer measurements of electrical components such as transistors and integrated circuits.
A probe sold by Cascade Microtech performs well in the transmission of test signals. However, the probe tip's contact surfaces are attached to a thin ceramic support which is stiff and fragile. This inhibits the probe's ability to conform to surface irregularties in the wafer and the tip may be easily broken. The probe uses coplanar wave guide transmission lines which are typically sensitive to geometry variations and is expensive to manufacture.
The present invention is directed to a Probe which is compliant and can withstand small deflections and impacts without breaking and can conform and make good contact with slightly irregular pad heights and which is inexpensive. The present probe utilizes a micro-coaxial cable or cables with simple non-lithographic fabrication techniques to create a probe with pads (signal/ground) with good high frequency performance.